OK, I've been working on this 93 945 non-turbo, owned it for a long time, but lately she's been uncooperative.

I have a driveline vibration that comes on at about 42 mph and ends at about 50 mph; otherwise all seems OK. No vibrations until after completion of the u-joints & center bearing job 9 months back. Obvious question is it out of alignment? I marked all pieces with paint, even put bolts back in same locations. Double checked at reassembly and several times since. Finally, took it to a shop I know and we studied it on the lift, thought maybe shafts were off 1 spline, shifted rear relative to front 1 spline to make sure u-joints were aligned (as discussed in FAQ). No difference.

What else have I done? New motor and tranny mounts (Volvo OEM), brakes overhauled as needed, no vibes there, made sure tires were balanced, all is well. Tried shimming center bearing support ~1/4 inch, no difference.

So, could this be due to a bad u-joint (not OEM), seems unlikely as they usually clunk or is it time to take the shaft out again and find a shop to balance. As always, any thoughts are appreciated.

Mike